Zwiebelkuchen is an onion pie from Swabia, in south-central Germany. It is a special time of year, in the fall, when the mom & pop winemakers will open a BasinWirtschaft in their barn or garage. They serve the new wine, fresh zwiebelkuchen, and perhaps some wurst, for a minimal fee. A few tables are set up, and they are open when they have time to serve. To indicate they are serving, they will hang a straw broom over the doorway. The combination of the onions and the 'green' wine can have explosive consequences later on!